Archive of Our Own

Dean used to think the bunker was weird.

He couldn't get used to sleeping in the same bed every night. The air conditioner wasn't loud enough. There weren't any sounds of traffic bleeding through the walls at all hours of the night. There weren't even any suspicious stains on the floor. 

That last one isn't actually a bad thing, but for some reason, it's part of the list of things that initially bugged him about the place.

He still shares a bathroom with Sam, but Sam sleeps all the way down the hall now—and even though he's gotten used to it, Dean still thinks that's too far away. His room is too quiet without Sam's little grumbling snores, occasional grunts, and the rustling of cheap sheets when he rolls over. That's another thing: the sheets are too nice. It's like sleeping wrapped in funeral home curtains. It used to keep Dean awake. And laundry. He hates the laundry. He was used to laundering their clothes, sure, all those laundromat things like baggies full of quarters, lint everywhere, reading old magazines in their skivvies. But now they have to wash their sheets, too. It sucks.

Sam doesn't seem to mind any of that stuff. In fact, Sam settled easily into domestic life. Within a few days, he was accusing Dean of nesting, with that little smug smile on his face that Dean can't stand—but he's the one folding his shirts into an actual dresser and sweeping the floor with an actual broom. While Dean begrudgingly began to enjoy having a kitchen and a scimitar and an actual (dead guy's) bathrobe—he just couldn't get over the weirdness of the place.

Now, it's old hat. After everything they've been through—the Trials, the angel Gadreel, Metatron, taking on the Mark of Cain to defeat Metatron; being murdered by Metatron, and turning into a demon as a result—Dean is glad to have a place to come back to that he knows hasn't changed. He doesn't have to burrow into a different cheap pillow every other night. He can make a decent burger in his own kitchen, watch a movie on his own laptop propped up in his own bed, and park his Baby in his own garage. He can almost call it—dare he think it?—home.

Sam seems to be happy with it, too. He's got his books, and his huge flat-screen TV, and a laptop finally free of Dean's accidental viruses. He putters around cataloging artifacts; he studies the bunker's systems. He tries—to Dean's disgruntlement—to figure out a cure for the Mark of Cain.

And Dean is happy for him. Really. He's happy that Sam has a place where he can do all that in his socks, where he can finally have some space to himself. He knows Sam wants that, has wanted it for a long time—he left them for Stanford because of it. Sam has always yearned for something more permanent than the hunting life could afford, and even when everything was going to shit, the bunker itself didn't change.

The only thing that's changed, really, is Dean.

He's not a demon anymore. The cure really did work. He had his doubts, right up until he was looking at Sam through eyes that wouldn't flash black again. He's free of that—and he's glad, because he was treating Sam and the Impala like shit, and they're the best things in his life, the only two constants he's ever had. But he's not free of the Mark.

Cain tried to warn him. He did. He told Dean it would all go to shit, and he was right, and he keeps being right. The Mark has wormed its way through Dean's body and heart—and as evidenced by his and Crowley's howl at the moon, it's got a bead on his soul, too.

And when everything else is quiet, it whispers to him.

Not in words. That would be too obvious, too easy to ignore. Dean has spent his entire life giving the finger to various voices that would tell him what to do. No, it's impulses. Feelings. Not foreign ones, either—the Mark just amplifies the darker things that already exist within him. It's a danger that Dean isn't used to. Although he thinks he can fight it—tells himself he can win—sometimes, it honestly scares him.

Not like he'll ever tell Sam that.

Not like he really even admits it to himself.

- - - - - - -

One night in particular, he's sitting in bed, propped up against the headboard with the covers pulled up over his legs. He's trying and failing to focus on a book he picked up at random at a thrift store because the cover looked cool, but it's turned out to be a drag, and he's only struggling through because you spent a dollar on it, dammit, you're gonna finish it. Sam keeps harping on about hobbies and too much down time, and Dean doesn't want to lean too heavily on the “I'm recuperating” shtick. That whole wacky fiasco with Calliope at the Catholic school kind of proved he's back in the saddle, more or less. All they're doing now is waiting for Cas to figure himself out, and in the meantime, find something to hunt.

His eyelids begin to droop, blurring the words on the page. Just as he's about to give up the ghost and call it quits, he hears a noise from the hall. He freezes, hand outstretched toward the bedside lamp. Keeping his breathing quiet, he listens intently, waiting for whatever it was to make another noise, or show itself.

The mystery resolves in the form of Sam, lumbering forward in his t-shirt and boxer briefs, rubbing his eyes. He must have woken up, noticed there was no threat to wake up for, and now he's wandering in to make it Dean's problem.

With a sigh, Dean sits back.

“You startled me, you little shit.”

No answer. Sam just stands there, squinting at him with the same grumpy look on his face that he'd wear when he was a kid and just woken up by a passing semi, or Dean rolling over too hard.

“Go back to bed,” Dean says with a wave of his hand. “I'm turnin’ in, too.” He leans over and pointedly snaps off the light.

Now, Sam is just a silhouette in the doorway, backlit by the soft, omnipresent glow of the bunker's ambient lighting system. The fact that he hasn't moved isn't as unsettling as the fact that he hasn't said anything. Dean lies down on his side, cheek on his too-soft pillow, curled into an apostrophe to keep an eye on his brother.

It's then that Sam moves.

Into Dean's room.

Softly, he pads toward the bed, toward the side where Dean lies clutching the sheet to his chest, still not saying a word. It's not until he's sinking to his knees, eyes wide open and focused on Dean's face, that Dean starts to say, “Sammy, what the hell's go—”

But the rest of the sentence is lost against Sam's lips. Sam's mouth, opening up and spreading Dean's lips with it, so Sam's tongue can flick its way in along Dean's and steal his ability to speak at all.

Dean's entire reality has short-circuited. He grabs at Sam's shoulder, his chest, to shove him away—but Sam shifts, taking advantage of Dean's lack of leverage to overpower the tension in his abs and stretch him out on his back. One of Sam's hands plants alongside Dean's head, then his elbow crooks and lowers him, so now their chests are pressed together and Dean is just hanging on for dear life. Sam's other hand cups his cheek. All the while, he's taking Dean apart with lips, tongue, and teeth. And Dean is barely hanging on to his sanity.

The Mark stirs. Previously content to lie as dormant as regular scar tissue on his arm, it twinges now, heating up to a smolder that stings. Itches.

It's saying, oh. What's this?

It likes things that are wrong, things abhorrent to the natural order—and this is that.

When Sam breaks the kiss, breathing hard, Dean stares up at him in slack-jawed wonder, ignoring the hell out of the ancient curse bleeding hot, wicked humor into his forearm.

“Sammy,” he breathes, “what the hell?”

Sam still doesn't say anything.

“Christo.”

No response.

But Sam does move. He moves down Dean's body, hands dragging, pressing, fingers digging in until Dean squirms. Dean remembers he has hands of his own, hands that can be used for shoving, just before he realizes Sam has dragged the covers down with him.

Hot breath settles over his cock, and Dean's already shortened circuits overload. The Mark flares, and with it, arousal so intense that sweat begins to prickle at his hairline. Dean isn't sure if the Mark is making him hotter for this than he would be anyway, because he's never had his brother's face this close to his junk before. He wouldn't have thought it would be hot at all, but hey, there's a first time for everything.

Wait. No, the fuck, there is not!

He scrambles back—”Sammy, what the hell?”—or tries to, anyway, but Sam has draped himself over Dean's legs, holding him immobile while he thrashes. Sam noses at Dean's cock through the cotton of Dean's boxer briefs, and now it's thoroughly invested in these proceedings.

Fucking traitor, Dean thinks. Even his thoughts are panting.

One of Sam's hands is splayed over his chest, and Dean can see the corded muscles and tendons in the arm it's attached to are poised. Ready. If Dean tries to struggle, Sam will just hold him down. That notion brings about a low surge of fury that Dean knows isn't his own. He was never furious when Sam pinned him during a spar—frustrated, sure, but not mad. He'd smack the Mark if he could reach it.

Sam's other hand fishes him out of his underwear.

“Oh, my God,” Dean whispers.

With a hum of satisfaction—the first sound he's made since he showed up, Sam licks up around the head of Dean's cock, takes it in his mouth, and sucks it down to the root.

Dean's head snaps back. Sam's mouth, oh, Sam's mouth. Jesus fuck. Sonnets and songbirds explode in his mind, sparks overlaying the darkened ceiling above him as he stares up through it, wide-eyed. Sam is bobbing his head, taking Dean deep and easy. It's hot, and wet, and it must have been too fucking long since Dean last got lucky because he is climbing that mountain at record speed.

“Sam,” he moans, strangled. “Mmph—fuck, Sammy—”

Another hum, this time on an upstroke. Sam is bobbing his head at an impressive speed, neck muscles working, shoulders bunched. He twists his head, sucking hard, running the point of his tongue up the underside of Dean's cock, and Dean is done. He's fucking done.

He comes with a sob straight down his baby brother's throat.

And Sam? Sam swallows.

“Oh, my God,” Dean groans, Sam's unexpectedly talented mouth working him through the aftershocks. By the time Sam pulls off with a satisfied smack, Dean's bones have turned to jelly. He's shaking. Oh, fuck. That's the best orgasm he's had in a long, long time. He's hot all over. Sweating. Something inside him does a pleased somersault.

Then the pressure on his chest lets up. Sam is standing, dragging the back of his hand across his lips. As silently as he arrived, he turns to leave. Dean can only watch him go. His mind is full of static, a wash of red, and the remnants of a very confused, very sated hallelujah chorus.

- - - - - - -

The next day, Dean cooks Sam breakfast. He really goes all out, too; quiche with a bunch of veggies, that tofurky bacon crap Sam bought, even fresh-squeezed orange juice. He serves it to Sam in the library, grinning, and gets a bemused smile for his troubles.

“Thanks,” Sam says in a cautious tone, like he thinks the other shoe is about to drop.

“Yeah, no problem,” Dean says. He sips his coffee. “Man, I haven't slept that well in ages.”

“Oh, yeah?”

Dean glances down. Sam isn't looking at him, he's fully concentrating on cutting his quiche.

Playing hard to get, huh?

“Yeah,” Dean says. “Must have been that, uh, late-night workout.”

“You were working out?” Sam pauses with his fork halfway to his mouth, eyebrows up. “What was all that about ‘man needs his beauty sleep, Sammy’?” His impression is spot-on, and Dean hates it. The Mark hates it, too. How dare he belittle me. “We went to bed at like, ten.”

“Yeah, we sure did.”

One eyebrow quirks higher than the other, and Sam eats his quiche. Dean watches him expectantly. But all he does is eat.

After a few bites, he swallows, and says, “What?” 

Dean startles. “What, what?”

“You're staring.”

Yeah, there's no helping that, Dean thinks. Sam is too nonchalant. He's not that good of an actor, not with Dean. He always caves. If it was a joke, he'd be laughing by now. Dean isn't sure if Sam would volley more innuendo or just scoff, but he'll take either one, because this studied ignorance is getting on his nerves.

“You didn't get out of bed for anything?” he asks. “Anything at all?”

Sam's nose scrunches. “No?” he says. “We both turned in around ten, and I woke up at six. You stayed in bed till seven. Then you made breakfast, which, dude.” He points his fork at his plate. “Yes.”

“It’s good, right?” Dean's mouth says automatically, his mind reeling. A very bad, very real possibility is dawning.

He doesn't remember.

Sam may have sucked his soul out his cock, but Sam doesn't remember doing that, because Sam was still asleep.

Oh, God. Oh, fuck.

It's been so long, Dean forgot that was even a thing Sam used to do. But he remembers, now, that when they were kids, one of the myriad reasons he slept between Sam and the rest of the room was because sometimes, Sam would try to get out of bed. He wouldn't respond to Dean's whispers, just shoved futilely against Dean's restraining hands until he gave up and laid back down. Dean tried to tell him about it a few times, but Sam just waved him off. If he didn't remember it, then Dean must be making it up to be an ass like he always was, right?

The habit seemed to be broken after Stanford—after all, nowhere was safe.

But now—

When they first moved in, Sam did say it felt like they were safe here, and Dean didn't think anything of it other than hey, yeah, it's warded to hell and back. I can sleep with my boots off. It was fine for a while, then it became a makeshift hospital during the Trials, and subsequently Gadreel's presence—and what he did to Kevin—tainted it, almost beyond repair.

But now—at least, to Sam's unconscious mind—it must be safe again, and that apparently means he can wander around in the dark and blow his brother.

Dean doesn't know what to do with this new information. He's already getting a headache just sitting across from Sam, watching him shovel bites of quiche and tofurky into the mouth that had Dean seeing stars just hours ago.

Well, one thing is for certain: Dean's not gonna tell him.

And Dean is locking his door.

- - - - - - -

If Sam notices he's acting weird after breakfast, he doesn't say anything. He caught them a case a few hours away, he says, and Dean nods like he's listening. He can't stop staring at Sam's mouth. Dirty mouth. Where did Sam learn all that? College? Stanford was a long time ago. Did Sam fuck guys? Does he fuck guys, like, now? How long has he wanted to fuck Dean?

If anyone had ever asked Dean, hey, do you want to sleep with Sam? he would have pulled a gun and asked them, hey, do you want some new holes in your face? It's not something he ever considered. Sam is home, Sam is family. Sam is protect, teach, scold, mend, train, feed. Sam is not a conquest.

Tell that to Dean's downstairs brain, though, which is now considering Sam in a whole new light and loving what it sees. He's used to Sam just being Sammy, the kid he raised, the snotty teenager he scuffled with in the dirt. But this Sam, adult Sam, is taller than tall, broad-shouldered, all lean muscle and sinew. He has hair like a male model and a mole by his nose that Dean has never once considered beautiful until now.

It's like every time he blinks, he sees a new angle to Sam's attractiveness. The kid hunches to make himself smaller and more approachable when they talk to witnesses, then straightens up and throws his shoulders back when they confront the person behind it all. Dean watches him move so intently while they fight the guy that he almost gets himself tossed out a third-story window for his trouble. The Mark doesn't like that at all, sending murderous impulses all throughout his system, but he's too distracted to care. Sam moves like a jungle cat, quick and stealthy till he pounces, jaw set hard when he fires the sawed-off and sends Mister Belvedeerstalker to the great beyond.

Hey, the guy was a butler who thought he was channeling Sherlock Holmes, which turned out to be a malevolent spirit that told him to kill people—but it turns out he didn't really care about that, and tried to kill the Winchesters instead letting them help him get rid of it. So they killed him.

Elementary, my dear Watson. Dean thinks it writes itself.

He's not really putting any thought into it. Too busy staring at Sam's hands—wide palms and long, slender fingers—which pause in the act of reloading the shotgun when Sam notices him staring.

“What?”

Dean's head snaps up. His eyes follow a beat later.

“Huh?”

Sam is frowning. “What's up with you lately? It's like you're not even here half the time.”

“What do you mean?” Dean sputters. He tosses his crowbar into the trunk. “I'm here.”

“No, you're really not,” Sam says, waiting for Dean to move the propped-up shotgun so he can slam the trunk shut. Dean also does this a beat too late. Sam's shirt is riding up, exposing the barest glimpse of pelvic cut.

With a sigh, Sam holds out his hand. “Gimme the keys, Magoo.”

“Whoa, hey! You ain't driving.”

“Then you better get out of your head, because I'd like to stay alive.”

They get in the car, slam the doors shut in tandem, and Dean adjusts the rearview mirror. He so pointedly does not look at Sam that Sam makes a disgruntled noise.

“Just drive. I want to shower.”

“He didn't bleed that much,” Dean says, putting the car in drive. The Impala surges forward happily, always seeming so eager to get back on the road.

“He tossed me into those rotting corpses. I smell like Hannibal Lecter's compost pile.”

Dean takes an experimental sniff. “Ugh. You do. Roll down the window, Clarise.”

He still doesn't look at Sam, but knows he got an epic eye-roll before the window opens and cool night air roars in.

- - - - - - -

“Is it the Mark?” Sam asks quietly, later.

“What? No,” Dean says. “I've got that shit locked down. Don't worry.”

Sam nods, but the furrow in his brow says he'll worry whether Dean likes it or not.

The Mark seethes. He should listen. He should obey. He has always been subservient to you, and needs to know his place.

But Sam's place is just within eyeshot, alive. That's all Dean really cares about. He focuses hard on it—and gets a wave of dark, nebulous impulse that feels suspiciously, annoyingly, like a scoff.

- - - - - - -

Dean can't sleep.

Part of him doesn't want to. Another part of him is afraid to. Yet another part of him hates that he's lying here in the dark, practically vibrating with anticipation.

All of him feels sick.

You gotta tell him, he thinks. You gotta wake him up and tell him. Wait, but didn't they say you're not supposed to wake up a sleepwalker? Like, it'd scare them to death or something? He looked it up once, a long time ago, when Sam's lack of response started scaring him. But that was two deaths and an apocalypse ago. Hell burned a lot of him away, and Purgatory wiped him clean. He should look it up again.

He reaches over for his phone.

The scuff of bare feet outside his door arrests the movement. Dejà vú washes over him in a nauseating wave. The Mark perks up.

“Sammy?” he ventures.

There's no answer. Not like he really expected one.

He considers whether he could maybe herd Sam back to his own bed, or something, without waking him up. Just gently take his hand and lead him like a lost child. He frowns. The idea of Sam as a virile adult is too entangled in the memories of Sam the chubby toddler, Sam the cooing baby. Sam, the lanky teenager hoisting a duffel bag and heading off to civilian life at Stanford.

Sam, flopping forward in his arms, dead. 

Sam, with his arms outstretched in the rushing wind at the edge of the pit like Jesus Christ friggin’ Superstar. 

And now, Sam, standing like a specter in his doorway, swaying on bare feet.

Dean should get up. He should. He should put a stop to this, he should help Sam, not take advantage of him. You're really gonna molest your baby brother? Are you that sick in the head?

He's not. At least, he didn't think he was.

The Mark hums soundlessly on his arm.

It's not sick. Is it?

Aren't I just taking care of him?

No! Get up, he wills himself, with increasing urgency, because any minute now Sam's hindbrain will walk him over here. He needs to swing his legs out of bed, walk calmly over to Sam, and gently guide him back to his own bed. Get up. He should resist this temptation. It doesn't matter how good the head was. It doesn't matter that he's spent all day wondering what those hands can do. It doesn't matter, goddamnit, that he wonders just how far this will go. Get up!

But like the coward he is, he doesn't move.

Sam does.

It's frightening, really, how smoothly Sam approaches, for all that he's asleep. And he's definitely asleep. When he grabs at the covers and slides in, Dean scrambling to make room, Sam turns to him and stares at him, and there's nothing behind his eyes. They're half-lidded and glinting in the low light of the hallway. Clearly, there's nobody home, and yet somehow, Dean feels known. Like even though Sam is basically unconscious on his feet, he instinctively knows exactly where he is. That doesn't really come as a surprise. Sam would probably know Dean in any universe; deaf, blind, and dumb, he'd feel Dean there and know. Dean knows this because he's the same way.

He knows this, just like he knows Sam didn't get under the covers to lie down.

The hands he's spent all day scrutinizing now cup his face and draw him in, close, closer, until Dean's eyelids slide shut and he's once more getting kissed within an inch of his life. He wonders, briefly, if this is what Sam is like with all his dates—precious few that Dean knows he's had—all confident and thorough; taking his time, but controlling every second of it. His lips and tongue take Dean apart bit by bit. Is there a limit to how many times a man can be disassembled like this, put back together by morning, before he starts to lose the plot of who he is? Dean doesn't know. He moans into Sam's mouth, finds Sam's face and digs his thumb into one sharp cheekbone, his fingers threaded through soft, long hair. His other hand fists in Sam's shirt.

Dean realizes he's hard when Sam shifts to press their bodies together, and he feels Sam's dick like a billy club against his thigh. He tenses his whole leg, offering himself for Sam to rub up on, and Sam takes the invitation up in a long, sinuous grind. He props himself up, rolling them until he's looming over Dean, still kissing him thoroughly. Dean is breathing hard through his nose. His hands are moving of their own accord, stripping Sam's shirt up and off so they can get a good double grip on Sam's shoulders. The muscles working under Sam's skin are taut and toned. He's the one who works out. He knows Dean doesn't. Maybe Dean should—then he could see all this in the daylight. But would he be able to control his body's reaction to that, after this?

He realizes belatedly that Sam is returning the favor, yanking his shirt up, and Dean struggles to help him. The instant it's out of the way, Sam comes crashing back down on top of him. Oh, God, but skin on skin is so much better. How did Dean forget? How is the sleeping guy the one who's making this awesome?

Then Sam's fingers start plucking at the waistband of Dean's boxer briefs, and Dean forgets to breathe.

I should stop this, he thinks, as he shimmies out of them and Sam tosses them away. I should wake him up. I should—

Then one of Sam's enormous hands finds his cock, and Dean is gasping, shivering, biting at Sam's lower lip. All of his thoughts fly out of the room and down the hall in search of the nearest window.

“Fuck,” he breathes into Sam's mouth. He gasps—Sam's grip is on the delicious side of tight, stroking him rough and sure, rutting into the cut of his hip. Dean's eyes are wide open, but all he can see of Sam is the way the light catches dully on his hair as it swishes when he moves, the dark hollows where his eyes glitter, and a dim outline along his shoulders. Sparkles of black and white begin to swirl and burst over everything as Sam works him over. Dean has never been this hard in his life. It's only a handjob—but it's Sam. No one else could possibly compare. And Dean had no idea. None at all.

His balls start to draw up. He can feel the promise of one hell of an orgasm prickling under his skin, down to his toes.

Then Sam lets go.

Dean makes a noise of protest—but then Sam's finger is delving down under his balls, along his taint, finding his hole and digging in, and the noise becomes a shocked little moan.

God, it's dry, it hurts, but he's never been more turned on. And he doesn't care, he doesn't care, he will let Sam take and take and do whatever the hell he wants. He will let Sam fuck him dry and bloody, and gladly not sit right for weeks. Right now, hard as nails and out of his mind with want, Dean is up for whatever, so long as it's Sam.

But he doesn't have to worry, apparently, because Sam is shimmying down under the covers, tossing Dean's legs over his shoulders, and following his finger with his tongue.

Dean's head snaps back, digging into the pillow, his mouth open wide as Sam licks into his hole like it's an ice cream cone. Broad, dirty swipes become a wriggling point that spears him open and has him panting, swearing under his breath, moaning high and as quiet as he can. He works his hips down on Sam's face, trying to get as much of that inside him as he can, grabbing at his cock. Sam's fitting a finger in beside his tongue when Dean jerks himself once, twice, and comes with a hoarse shout he tries to muffle with his forearm. The Mark is hot against his lips, searing, stinging, and he bites down on it with a growl, tears springing to his eyes because it hurts, fuck—but he's still coming, pleasure in spinning waves like a hurricane, over and over until he's spent. Sam is still licking him, and Dean tries to move his legs off Sam's shoulders, tries to shove him away, but he's mid-movement when he realizes two things: Sam is making the most delicious, strung-out noises, and the bed is vibrating, hard. Sam is jerking off. Sam is getting off on eating him out. Dean's cock blurts out another splotch of come. God, this is so wrong, and so fucking hot.

Sam comes with a long, agonized groan pressed into the deepest part of Dean, shuddering hard, grinding what is probably a colossal mess into his underwear and the mattress. Dean holds him there with his thighs and lets Sam dig his face in, lets him suckle the tender skin, until Sam is lying there gasping and not moving much at all.

Carefully, Dean lifts his legs off Sam's shoulders. Sam slumps down on the bed, and as Dean gets into more or less a sitting position, he hears Sam snore.

Son of a bitch, he thinks, annoyed but oddly proud. Look at that.

He manages to find his shirt, and wobbles his way to the sink, where he wets it. Then he carefully maneuvers Sam's face so he can wipe what he can from Sam's mouth and nose. Man, but this will be hard to explain in the morning.

He's hanging the shirt up to dry when he hears a snort. He turns to see Sam sitting bolt upright, staring around at nothing.

“Sammy?” he ventures.

But Sam doesn't react.

“Shit,” Dean mutters. Slowly, he moves over to the bed, and begins the laborious process of getting his mountain of a brother back to his own room. “C'mon, let's go.” He glances behind them. “You made one hell of a mess.”

Misplaced blame if there ever was any—but while Dean may only have a G.E.D. in textbook education, he's got a doctorate in denial.

His forearm aches, deep bitten grooves dug in around the sickle-shaped keloid of the Mark. It burns whenever he touches Sam, like it recognizes now that this is a perfect source for the deeper, hotter emotions it feeds on. By the time Sam is safely ensconced in his own blankets, snoring away, the Mark is glowing like a fresh brand on Dean's skin. The stench of burning meat fills his sinuses, reminds him of pyres, of jobs gone wrong and lives left ruined.

It follows him down into restless dreams.

- - - - - - -

He wakes the next morning to the far-off sounds of running water and spitting.

Poking his head around the bathroom doorway, he sees Sam grimacing in the mirror, toothbrush in his mouth, foam dripping down his chin. Dean follows his head with the rest of his body. He steps up to the other sink, the one with his toothbrush, and glances aside at Sam.

“Morning breath got you down?”

“Ugh,” is the garbled reply. Sam fills his little cup with water, swishes a mouthful hard for a moment, then spits. “My mouth tastes like ass.”

Dean almost chokes on his toothbrush.

- - - - - - -

Days and nights go by, and nothing else happens. They've been thrown headfirst into a new kind of trouble, again, and they both sleep as deeply as they can when they get a chance. The nights not spent tossing and turning, Dean spends watching the doorway from his pillow, wondering into the wee hours of the morning if he'll ever get another surprise.

Thankfully, the world going all to hell around them means there's no time for self-flagellation. He doesn't have to think about the fact that he's a piece of shit who took advantage of his brother in a vulnerable state—twice!—and that if Sam ever finds out, Sam will—and should!—leave his sorry ass for greener pastures. He's not touching it with a ten-foot pole, but he doesn't have to. He knows it's true. Knows he'd deserve it.

You would. You deserve every rotten thing that comes to you. You're a mess that needs to be put out on the curb with the garbage.

He's not sure if that's his conscience talking or not, but he's inclined to think it's right. However, it can shove it. So whenever guilt crowds to the forefront of his brain and insists he just come clean, give Sam a chance to take his agency and run, he shoves it back down in the void and tells it to stay down.

And in the meantime, he looks at Sam.

Sam, with those little quirks of his mouth whenever Dean makes a bad joke, those vibrant hazel eyes, those hands that Dean can't stop watching as they deftly disassemble a gun to clean it, reassemble all the fiddly pieces, and click the stopwatch in front of him. Another mouth quirk. This one is dissatisfied. Sam clicks the stopwatch again, begins again, while Dean pretends to be watching a video on his phone and instead watches Sam like a perv.

It's getting easier to separate baby brother from object of desire, although when he's drunk he can admit to himself that he doesn't want to make a distinction. He foggily examines it and realizes that if it were any other guy, that guy would be nursing bruises and broken bones from the first time around, and there wouldn't have been a second. It's the fact that Sam, the guy he's been soldered to ever since Dad shoved the little bundle of him into Dean's arms, feels safe enough with Dean and their current living situation to—what? Give into baser urges? Sleep without a gun under his pillow? Nah, he bets Sam still does that. Old habits die hard.

Weeks go by, life charges forward. The Mark gets harder to ignore, but Dean tells himself he's got it under control. He starts going to sleep earlier and earlier, both to shut that thing up and to try to stop anticipating anything happening in the dark. Nothing does.

Sam got it out of his system. It's over.

Dean doesn't let himself examine the fug of disappointment that settles when he finally starts to accept that.

- - - - - - -

At some indeterminate wee hour, he sits up with a sharp inhale through his nose, yanking his gun out from under his pillow and cocking it before he's even awake. He aims at the doorway, but nothing comes through. Squeezing his eyes shut, blinking wide a few times, Dean listens hard. There's nothing to indicate what woke him.

He un-cocks the gun and slides it back where it belongs.

Then, he hears it.

A long, drawn-out groan.

It doesn't sound sexy. It sounds like Sam is in pain.

Dean will murder whoever, or whatever, makes his brother make a sound like that. He will. He's up in a flash, feet thumping on the cold concrete, making a mad dash for Sam's room only to slam to a stop in the doorway, gripping either side of it. Staring.

Sam has tossed the covers on the floor. He's also apparently taken to sleeping naked, because he's flat on his back with a raging erection and Dean can drag his eyes up the whole girthy length of it.

And drag he does. Hoo, boy. Just a few weeks ago, he thought he could take that thing dry? He'd probably still be in the hospital.

Dean swallows hard. His mouth is watering, and he can't take his eyes off it. He wonders what it would feel like, to wrap his lips around it, suck every inch he could, jack the rest with a free hand while he went to town on himself. He wonders what it would taste like.

The tip glistens in the low light. Sammy's getting wet.

Dean's forebrain goes offline.

He's never had a cock in his mouth before, but he figures Sam's still tastes the best, salt and skin, the bitter tang of his precome. He's even bigger up close, bigger still between Dean's lips, and Dean bites back a moan when Sam surges up to meet him with a strangled, sleep-muddied cry. He gets that thing as far down his throat as possible, digging around in his underwear and getting a tight grip on his dick, which is harder than he expected. Oh, but he's ready to go. So ready. 

He plunges down again, gets his other hand wrapped around the inches he can't take without gagging, and sets up some kind of rhythm between his hands and tongue. Bob, suck, lick around the head. He drags the point of his tongue hard up the underside, then again, just to hear Sam keen when he does it. It's hard to look up, but he does, once or twice, just to see Sam arch his back and claw at the sheets, tossing his head on the pillow.

Dean is fully ready to accept what he knows is coming—wants it, wants Sam to blow down his throat like a geyser, till Dean can't take any more of it and it runs down all over his chin. He feels the pressure and pull of his own orgasm looming, speeding his hand up, breathing hard out his nose the faster his moves his head. Every breath Sam takes now leaves his lips as a moan, and his hips are working like engine pistons on the home stretch of a race.

“Mm hm,” Dean hums around him, as best he can, encouraging with his eyes squeezed shut.

He comes first.

It hits him square in the nuts and he doubles over, jamming Sam's cock into his esophagus, but it's fine because he's not breathing, he's pumping his soul out into Sam's blankets. Pulse after pulse hits him and he's holding on for dear life, no air, no thoughts, just pleasure so intense he might drown in it.

When Sam comes, Dean doesn't even taste the bitterness, just feels it boiling hot and thick down into his stomach. It sets off a chain reaction of new pleasures, pains that tingle and flash. He's groaning so loud he's not sure how Sam isn't waking up.

Why isn't Sam waking up?

Gasping, shaking, Dean pulls Sam's cock out of his throat and tumbles onto legs that won't hold him, lurching half-naked and still leaking up to Sam's head to check if he's still alive.

He's breathing. But he's out cold.

Dean knocked him from sleep to unconsciousness with the hummer to end all hummers. Oh, man. Oh, wow. He stares down at Sam's slack face with pride. Every nerve in his body is singing. He feels like he could conquer the world, but also like he really, really needs to sit down.

He can't be in the room when Sam wakes up—because when Sam does wake up, he'll probably be confused as to how his spunk ended up under his ass instead of all up his chest. 

Hopefully, Dean thinks as he crawls back into his own bed, weariness wrapping him up tight, he'll just think he rolled over.

- - - - - - -

The next evening, he's sitting in the library with a rocks glass in one hand and his phone in the other, watching Sam read some enormous leatherbound artifact of a book. There was no ruckus about any messes, so he figures Sam took it in stride. Another wet dream. Normal guy stuff. There was less than zero reason to suspect that the puddle of spooge you woke up in belonged to your brother.

As Sam carefully turns another page, Dean lets his mind's eye wander back over what he knows that baggy t-shirt and equally ill-fitting pair of jeans are hiding. More specifically the jeans, but Dean is not opposed to running his hands all over Sam's upper body, too—dragging his flat nails down over Sam's nipples to make him squirm, licking every inch of him until he's panting for more.

Dean feels hot and prickly all over. He might be turning into some kind of addict. 

Watching Sam, he thinks that maybe, that's just fine.

A frisson runs down the back of his neck, and hastily, he turns his eyes back to his phone screen, which has been open on a NSFW subreddit for so long that the enormous anime tits he was ignoring are probably burned into the screen.

“Dude.”

Feigning nonchalance, Dean glances up to see Sam frowning at him.

“Huh?”

“Quit looking at porn on your phone and come help me out. I think I'm onto something.”

Not only did Sam not catch him staring, but now, Sam wants him to move closer? Pocketing his phone, Dean makes a show of stretching, letting his shirt ride up above his waistband.

But when he peeks to see if it worked, all he gets for his efforts is a roll of those hazel eyes.

So he plays nice, rounding the table and plopping into one of the chairs beside Sam, scooting it closer with a heavy screech until he can lean in and look at the page Sam is offering for him to read.

The problem with that, though, is that with Sam this close, Dean can smell him. His shampoo, sure, and their laundry detergent, but also that unique blend of sweat and pheromones that Dean would know anywhere as intrinsically Sammy. One deep breath, and he has to fight to keep his eyelashes from fluttering like a damn girl's.

Sam is talking about whatever he just read, and Dean is nodding, trying to sound interested, but he's not retaining a single word. With every fiber of his being, he's resisting the insatiable urge to grab a double handful of Sam's hair and bury his face in it. It'd be so soft. It'd smell so good. He'd grab Sam and manhandle him into his lap, yank his face down and kiss him until he's—

Shit, Sam is frowning up at him.

“So you think it'll work?” Dean asks, hoping that goes with the flow of whatever the hell Sam just said.

“Uh… yeah.”

“Good,” Dean says. “Get crackin’ on that in your lab, then, Dexter. I gotta hit the head.”

He can feel Sam's frown following him as he stands and makes a beeline for the stairs, but if he doesn't get a hand on himself right fucking now, he won't be able to resist the fantasy. The Mark is fairly humming on his arm. In his head. It's in his head, and it's telling him that grabbing and taking whatever he wants is perfectly fine so long as he wants it bad enough.

Shutting his door, he plucks at his jeans till they pool around his ankles. He doesn't even make it to the bed. Hand shoved into the waistband of his boxer briefs, he grabs at himself, biting down on a shaky moan at how good the touch feels. Fuck. He grips hard, starts stripping his cock with quick, brutal strokes, and it's only a minute or two before he's coming with his mouth wide open, no sound. Stars in his eyes. He staggers, losing his balance, and it's only years of honed reflexes that have him collapsing on his bed in a heap with barely a sound from the frame. A sound which Sam undoubtedly heard—but who knows, maybe he's thinking Dean is just slacking off, not something that rhymes with it.

This isn't sustainable, he thinks. His libido agrees with him, already raging for round two. He's not satisfied with this. With waiting. The next time Sam wanders in here—and he knows there will be a next time—he'll be ready for more.

And he'll make sure he gets it.

- - - - - - -

There's no way to predict when it will happen again, but that's okay, because he needs to practice. He's never opened himself up with intent to take it up the ass before. Hell, he's never really paid that much attention to anal fingering in general. Good thing he's got a lot of decent porn sites on tap to mine for tutorials.

That night, after he and Sam brush their teeth and head to their separate rooms, Dean puts to use what he's learned. He turns off the light before he strips—figures he better get used to doing this stuff in the dark—and then, naked, gets on his back on the bed. In the videos, the guys would just pull their balls out of the way and reach down between their legs. He's not sure if that's because it's easiest, or because it looks the hottest.

He gets his fingers wet with lube and reaches down, angling his hips up for better access. When the first knuckle of his middle finger slides in easily, he stares up at the ceiling, mouth forming a little “o.” His nerves are burning. He knew he'd like it, but he thought maybe it was just because it was Sam, in the heat of the moment, not something he'd be into all the time. He had no idea he'd like it this much. None. But he does, and he wants more.

Before he can blink he's stuffing himself full of two fingers, panting, whining as quietly as he can, strangling the base of his cock so he doesn't come when he brushes over his prostate. Speaking of which, porn had been really, really educational in that respect. He had no idea guys had a g-spot up in there. It's unlike anything he's ever felt before. Girls feel this way when they do it? Fucking hell. He's so hard, he might die.

A moan threatens to break containment. Dean nearly punches himself in the face with the speed at which he bites at his fist.

Goddamn, he thinks, mindless, adding a third finger and working artlessly around in there. Goddamn.

He's not even sure Sam will show up tonight, and honestly, if Sam doesn't show up soon, Dean will probably end up accidentally giving himself the best orgasm of his entire life simply because he won't be able to stop.

But he's not paying attention to the doorway.

The bed dips and suddenly a body is covering him, a hand grabbing clumsily at the one he's got buried in his ass, and the shock of it is instantly soothed, smothered, stoked into renewed heat and desire when he smells Sammy.

“Oh, God,” gets punched out of him, gutteral. “Sammy—”

He feels something soft, with hardness just behind it, probe around where his fingers were about an instant before that something finds his hole, tests the give of it, and punches in. Hard.

Sam's body settles over Dean's with authority as his cock splits Dean wide open, and Dean can't help the animal noise that comes tearing out from deep inside him. Christ, Sam is huge, thick and long and perfect, and he's already snapping his hips forward. No time to adjust. Sam is hammering away at him like a dog in rut. All Dean can do is get his legs around Sam's hips, his arms around Sam's shoulders, and get fucked within an inch of his life. Sam is huffing in his ear, deep grunts and air. Other than that, he's not making a sound. Dean can hear, with piercing clarity, the way they collide each time Sam spears him open.

Dean fucking loves it. He ignores the burn of the stretch because he needs all of Sam's cock as deep as he can get it. Feels like yards of hot, smooth iron all the way up into his guts. Feels like the best fucking thing Dean's ever done. Sam is so deep inside him, he can taste it.

“Sammy,” he whines, trying to keep his voice low, but he can't not make noise because this feels too good to be true—”Fuck, Sammy, fuck, oh my God—”

He stuffs his fist back in his mouth, grabbing onto Sam tighter with his lube-sticky hand. He has to stop now, before he's mindless and starts screaming with how good, how deep, hard and thorough Sam's fucking is, it's blowing his fucking mind—God, oh God, he has to stop making so much noise.

Because if Sam wakes up—

Hell, if Sam wakes up, he won't have to kill Dean. 

Dean will drop dead underneath him from overwhelming embarrassment, need, and whatever else he'll be feeling if Sam stops fucking him.

“Don't stop,” he whispers, garbled, around his fist. Spit dribbles down. He doesn't care. All he can smell, taste, feel is his brother, and this, this all he wants.

Fuck. Where has this been all my life?

Right here.

Sam is working away mindlessly, shoving up against that awesome spot inside him that feeds him burst after burst of pleasure, and when he worms a hand into the complete lack of space between them so he can grab his cock and jack it furiously, that makes it so much better. So much. God, he's overwhelmed—love for Sam, love of this, what they're doing—

What you're doing to him.

Dean is too busy coming his fucking brains out to notice that he's also sobbing, tears running down his face, his hand working overtime to wring every last drop of come out of his body as he shakes, and shakes.

Above him, Sam startles violently, every bit of him contracting as he comes deep inside Dean, painting his insides hot and wet—

—at the very instant Sam wakes up.

“Dean?” he exclaims, rough and terrified. “Dean, what the hell?”

There's a stone in Dean's stomach, right where the tip of Sam's cock was ramming home just moments ago. Sam is still inside him but softening rapidly. He stares up at his brother in the dark, wondering if Sam can see the dread on his face, and realizes Sam can't the moment he says, 

“Dean? Are—are you okay? What the fuck is happening?”

There it is. He could weep anew with relief. Sam doesn't know it, but he just gave Dean the most flawless out possible. All he has to do is pretend he doesn't know what's going on, and it'll all be fine. He knows better than anyone that Sam is far more susceptible to suggestion when he's heartbroken. He can play this tune on this instrument. Just give him a starting note.

So Dean puts his back into it, says—

“Sammy? What the fuck?”

—and he scrambles back, yanking himself off Sam's cock as Sam is rearing back away from him, hissing when it catches nearly dry on his rim. Sam scrambles back to the foot of the bed, to the edge. In the dark, he looks like a cowering beast. Dean supposes he feels like one, too.

The heat of the Mark swims lazily through his veins.

“Oh, God,” Sam whispers, high and terrified. “Oh, my God.”

Dean ignores the way that tone makes his heart fall and shatter into a million pieces across the stone in his gut, because this is best. This is way better than trying to explain how he's come to feel, why he's been staring, and what started it all. This is better than owning up to what he's done.

He's stubborn about a lot of things, but when it comes to debasing himself versus losing Sam, there's no contest.

“Sam?” He's proud of the manufactured tremor in his voice. It sounds real. “Were you just—”

“I—”

Sam sounds like he's hyperventilating.

“Dean, I swear, I didn't—”

“Were you fucking me?”

Sam sobs. It's a deep, loud, gut-wrenching noise that Dean has never heard him make before, and hopefully never will again. He's breathing way too fast. He's having a panic attack. Dean is the lowest piece of shit on the shit ladder, leading down to the shittiest tier of hell.

“Sam!”

He lets Sam throw himself off the bed and stagger away. Listens to him break into muffled sobs in the hall. Bites his arm and tenses every muscle against the ingrained urge to rush out there and comfort his baby brother, to maim whatever hurt him, as he hears Sam's primal sadness fade into his room, into the slam of his door. There is no silence. Despite the thick wood, he can still hear when Sam starts screaming.

You ought to put a bullet in your damn fool brain and end it, part of him thinks. He's not sure which part. He's not sure whether or not he agrees. Goddamnit, you're the stupidest sick fuck who ever lived.

But he's a sick fuck who just came his brains out, so he falls asleep quickly, and sleeps like the dead.

- - - - - - -

The next few days are torture.

Dean has to keep up appearances. Has to act like he knows why Sam is miserable and thinks Sam deserves to. He forces himself to ignore the residual guilt that festers worse whenever he sees Sam's red eyes, or hears how hoarse Sam sounds giving one-word replies to everything. Committed to the bit, Dean answers any overtures into conversation, or apologies, with one-word replies of his own. As time goes on, Sam spends less and less time in the common areas of the bunker, shutting himself up in his room. Dean never hears music or the TV. The crack under the door is always dark.

His brain and his heart alternate between urging him to come clean—it's gone far enough, you piece of shit, put him out of his misery—and to kill himself. It's gone far enough, you piece of shit. Put you out of his misery.

One thing is for sure: he's gone too far. There's no going back. Post-nut clarity is a bitch under the best circumstances, but this? And having to lie about it afterward, probably for the rest of his life? It's fucked up. It's beyond fucked up. It's exhausting.

Who cares if you're exhausted? his mind berates him. You deserve it. You violated your baby. He's your baby, he's always been your little boy, and you just took and took from him without any cares about anything but yourself. 

Dean finds a full bottle of whiskey, then, and sets about making that voice shut up.

- - - - - - -

Later, Sam finds him in the kitchen. The bottle is empty, and Dean is drunkenly playing the knife game with his fingers splayed wide. He's already cut himself twice. Blood stains the notches he's making in the wood.

“Dean? What the hell?”

The knife is snatched away.

“What do you think you're doing?”

Dean lolls his head around, regarding the two Sams blearily.

“It's just a game,” he slurs. He's not sure if he means the knife, or life itself.

Sam tosses the knife across the kitchen. It clatters somewhere around the stove.

“Don't be stupid,” he snaps. He plucks at Dean's shoulders. “Come on, up. Get in the shower. You're embarrassing yourself.”

Upon trying to stand, Dean discovers that the room is now a tilt-a-whirl, and the trash can is almost too far away. He manages to get most of the whiskey—and not much else—into it and not all over the wall. And the floor.

“You're ridiculous,” Sam mutters.

But he doesn't touch Dean again. Just herds him toward the bathroom with looming presence and glares when Dean tries to deviate from the course. The minute Dean sets foot in the bathroom, Sam disappears.

The shower is nice. Hot and steamy. The cuts on his fingers sting, but that's fine for reasons he can't articulate. The water feels cold on the scar of the Mark. Dean's head graduates from swimming to pounding, and he throws up again in the toilet, still dripping wet. There's nothing in there anymore, but he dry-heaves until his abs hurt. When it's finally over, he doesn't try to get up. Just slumps across the porcelain bowl.

He must have passed out there, because next thing he knows, a towel lands unceremoniously over most of him.

“Dry yourself off and get in—” Sam's voice cracks. “Get out of here. You're a mess.”

“Ugh,” Dean says. You have no idea.

- - - - - - -

He doesn't remember getting to bed, but when he wakes up, his whole body reminds him about the whiskey. Christ, but he hasn't had a hangover this bad since he was a teenager.

Sitting up is a chore, but he manages, and braces himself on his thighs. He glances over at the doorway, which is blurry, because his eyes feel like they've been wrapped in several layers of cellophane. The door is open.

He wonders where Sam is.

It takes a couple tries, but he staggers to his feet, knocking back a couple of Excedrin and wincing hard when the sharp movement of his head makes everything sickening again. His stomach warns him that any more movement will result in the waste of those Excedrin, but he downs the rest of his glass of water and makes his unsteady way out into the hall.

“Sam?” he calls. Man, his voice is rough. He sounds like if Castiel ate a bucket of rocks and rubbed his vocal cords with sandpaper. Speaking of Cas—all the angels will probably disown him if they ever catch wind of what he's done. 

Righteous man, my ass. Self-righteous, maybe.

Ugh, that inner voice again. A whole bottle of whiskey wasn't enough? Any more and he'll die of alcohol poisoning—but then again, that might not be so bad. 

“Sammy?”

“Library,” comes the faint reply.

Dean makes his suffering way down the stairs to find Sam sitting at the table, staring hard at a laptop screen so bright Dean has to shield his eyes.

“Whaddaya have that thing set to, the sun?”

Sam turns, frowning at him.

“What?”

No answer. Sam turns back to the thousand-watt screen, scrolling whatever enormous wall of text he's reading.

“Whatcha reading?” Dean asks, sidling closer.

Quickly, Sam slams the laptop shut, and whirls on him.

“Why do you do this to yourself, huh?” he snaps. “It's not healthy. Drinking this much all the time fucks with your system, and your—” He falters for the barest instant. “—your sleep patterns, and it'll make your body do all sorts of crazy things.”

Dean squints. His heart is pounding. “Like what?”

“I—I don't know!” Sam says, exasperated, tossing his hands up. “Crazy stuff. But it's because your organs are failing, Dean. Do you want your organs to fail?”

The appropriate response to that is definitely a shrug.

Sam makes a disgusted noise.

“Come back to bed with me,” Dean's mouth says. He blinks, because he definitely did not give it permission to do that. He's frozen, watching Sam's face do some gymnastics. His mouth, apparently emboldened by its outburst, continues with a softer, “I want you to.”

Sam is looking at him like he doesn't recognize what he's seeing, eyebrows up to his hairline in an upside-down vee, mouth hanging open, lip trembling. His fingers on the back of his chair are pressing white into the wood so hard he might leave dents.

“What?” he says, barely any sound to it.

“I, uh.” Dean is back in control now, and has no idea how he's going to wrangle this. The pain pills have not relieved one ounce of his hangover—and since they have caffeine in them, he still feels gross, just faster. “I…”

The only way out is through.

“...want you in bed with me?”

“Wha—” Sam looks like somebody just told him he had to kill a kitten. “Why?”

“Because,” Dean says helplessly. His traitor mouth takes over again. “You were sleep-walking and came into my room and blew me, and then another time you ate my ass and we almost fucked, and then we did fuck, but you woke up so I pretended I didn't know what was happening so you wouldn't… think I was…”

He trails off. Sam has gone completely white.

“Yeah, I don't know why I did that,” Dean finishes lamely. “I'm, uh. I'm gonna—” He's jerking his thumb back toward the stairs when Sam's chair screeches across the floor and Sam is striding into his space, looking murderous.

Dean fully deserves the punch that knocks him to the floor, all of Sam's strength behind it. He deserves it when Sam straddles his chest and slams his head once, twice, three times into the concrete with a brutal snap of fists. There's a snarl on Sam's face, and tears in his eyes. Dean did that.

He's yanked up by his shirt front and shaken, hard, his brain rattling around in his bruised, hungover skull while Sam screams at him.

“What the fuck is wrong with you? Do you know what I've been putting myself through? For days?” Sam throws him back to the ground, hard. “I thought I violated you! I thought I fucking raped you, Dean! And now you're telling me I—and you—”

With a wordless roar, Sam wraps a hand around his throat and lifts him back up like that. Dean somehow always forgets how big Sam's hands are until they're being used in a way he doesn't expect. Hot, callused, nimble fingers dig in and grip tight.

Dean can't breathe. He doesn't really care, because he doesn't need to. There's nothing he can say in his defense. The void in his chest is yawning wide.

“I could kill you right now!”

“You should,” Dean says, or tries to, with split lips and what feels like a few loose teeth.

Sam lets out a short, hard huff of breath. Drops Dean hard enough to ring his bell against the floor again. Then Sam stands up, dusts himself off, and leaves. Dean hears the jingle of keys and the slam of a door in the direction of the garage, then far away, the telltale growl of the Impala.

Good. He can have her. He should, Dean thinks muzzily as unconsciousness shows him more mercy than he deserves.

- - - - - - -

He doesn't know how long he lies there, floating in and out of awareness, all of him throbbing with his heartbeat. He's hurt, really hurt, but he doesn't care. Sam's gone.

At one point, Dean opens his eyes. They fix on the scimitar, proudly displayed on its rack beside the bookshelf. He knows how many pounds of pressure it takes to separate a human head from its neck, and he figures he has enough strength left in him to make it happen. It'd solve this Mark shit, and set Sam free. He should do it.

But everything goes dark again before he gets up the impetus to stand.

- - - - - - -

“You fucking idiot.”

That's Sam's voice. Sam! Dean opens his eyes with great effort. All he can see is the floor, at first, but then Sam's boots come into view. Dean groans. It feels like his whole head is one big broken bone. The throbbing is so intense it's clacking his teeth together when he says, thickly, 

“You came back.”

“Of course I came back,” Sam says. He crouches beside Dean, very carefully grasps his head to examine his injuries. His mouth is set in a firm line. Dean just blinks up at him with heavy, swollen lids. He probably has a concussion, and he sees Sam consider this, but it's not like it's his first. He'll be fine. He's barely got any common sense, anyway, so if he gets a bit stupider after this, it won't make any difference. He thinks Sam probably knows that. Hell, he thinks with a sluggish surge of disdain, Sam has probably thought he was stupid as fuck for a long time now. He's certainly been acting like it.

Which of us acting like what? He doesn't know. Both, maybe? Yeah, both is good. Bad. Whatever.

Ignorant of Dean's internal angst, Sam sighs. “I took a drive to clear my head, okay? I was only gone about four hours.”

It seemed like an eternity to Dean, but then again, he wasn't exactly paying attention to the passage of time while he was wallowing in well-deserved pain, and what was definitely less-deserved self-pity.

“Can you stand?” Sam does so himself and steps back a foot or two. From Dean's position on the floor, Sam looks as tall as the Empire State Building and twice as imposing. 

“Ugh,” is all the response Dean can give.

Sam sighs. “I'll get you an ice pack.”

Turning his head, grit scraping against his scalp on the concrete, Dean listens to every sound Sam makes as he leaves the room and heads to the kitchen. He strains for each tiny clang and slam until bootsteps grace the floor by his head again. His whole body aches from the beating; his heart aches for Sam, and his forearm aches as the Mark urges him to pitch an almighty fit about it.

Something heavy slaps the side of his face. Immediately, blessed chill begins to seep into his bones, soothing the pain. He doesn't even care that Sam dropped the flat cloth pack from standing height. It feels amazing.

“I'm sorry, Sammy,” he says from beneath it.

“You know, I don't really believe that?” Sam replies. Beneath the pack, Dean frowns—but if Sam can see, he ignores it. “I think at one point in our lives, you might have meant it, but you also wouldn't have done what you did the other night.”

A scraping sound across the floor, then a soft thump. He's pulled a chair out from the table.

“You told me, when we were kids. You said I would sleepwalk sometimes.” A little laugh, no joy in it. “I remember thinking, nah, couldn't be me. All I wanted back then was to stay in one place long enough to feel like I had a place. Why would I get up and leave?”

Dean's head is throbbing less now, so he decides to try sitting up. With monumental effort, he gets himself propped up on his hands, then shoves up into crossed legs and a hunched back. He presses the other, cooler side of the ice pack against his face.

“And I think you really did care, back then, about making sure I didn't hurt myself. You shielded me.”

“Course I did,” Dean retorts.

“And up until last year, I think you still would have,” Sam says, continuing on like Dean said nothing. “But now? With the Mark? I guess I'm lucky I even survived.”

The ice pack falls away. Dean gapes up at Sam.

“You think I'd kill you?” 

Sam regards him steadily. His eyes are puffy around the edges, but his lips are pursed thin.

“I think,” he says at length, “that if push really came to shove, you wouldn't be able to help it.”

“Sam—”

“It doesn't matter that you're not a demon anymore. That thing has changed you, like, intrinsically. You may be human again, but you're not you.”

There's nothing Dean can say to that, because he can feel it happening. Sam is right. He's known for some time that the Mark doesn't seethe and burn to create new feelings; it just turns up the heat and boils the contents that are already in the pot. Dean's own rage, self-loathing, hedonism—a soup composed of all his worst traits, and the Mark is sipping on it with glee.

He never told Sam what Cain said, about how he's fated to murder his brother. Never told him, because how can it be true? Dean loves Sam so goddamn much. But now, he's getting a true glimpse of the way it might go down. Too much love, he's heard, is toxic. Poisonous. Too much passion leads to crimes.

“You're right,” he croaks. “I'm a shit human being.”

Sam snorts. “This isn't even the sixth worst thing you've done.”

“Oh yeah? What are the other five?” 

“I don't know, I don't actually have a list!” He's lying and they both know it; they both have lists and they've both hurled them at each other. But that's not the point. “The point is—look, I was going to say we need some time apart, but I know that if I leave you alone, you'll just go off the rails on somebody else. I can handle it. I'm the only one who can.”

You shouldn't have to, Dean thinks at the same time a darker impulse sneers, no, you can't.

“This thing I found, this Book of the Damned, it could cure you. Then all the rest of it will be fixed too.”

Not us, Dean thinks. Not this.

“Even this.”

Dean drapes the now-lukewarm ice pack over his knee.

“Okay,” he says. “Where do we start?”

Some of the shadows behind Sam's eyes clear; not all, but enough to give Dean hope.

“Rowena.”

“Ugh.” That name leaves an instant bad taste in Dean's mouth.

“I know. But so far as a source for all things witchy goes, she's our best bet.”

Sam stands, and seems to consider something for a moment before shrugging and offering Dean a hand. Dean takes it. Lets Sam haul him to his feet, and clap him on the shoulder—though judging by the way Sam immediately puts distance between them, that last part was just out of habit.

“Come on,” he says, “get yourself cleaned up. We got work to do.”

“Anybody ever tell you that you forgive shit way too easy?” Dean teases. 

Sam stares right through him. “I haven't forgiven you.”

It takes Dean a minute to process that. When it finally gets through, he thinks of a million things he could say: But I apologized.

But you liked it.

But you feel the same way about me. Don't you?

He doesn't say any of them. Just nods.

“That's fair.”

It may not feel that way—but it is. So he walks his sorry ass back to his room and shuts the door.

- - - - - - -

Days pass. Sam has taken to sleeping with his door closed. It feels unsafe. Dean understands, on some level, why Sam finds it necessary—but when he tests it and finds it locked, his mind instantly feeds him about twenty different ways that could end badly. Electrical fire. Carbon monoxide. Shtriga, again, somehow, despite Sam being in his thirties. But Dean, despite all these concerns, knows he has to let his brother do what he has to in order to feel safe—and even if it rankles, Dean can't argue with the results. After all, it's been his purpose in life since he first learned what purpose was: keep Sammy safe.

He tells himself that's why everything happens the way it does.

Some nights after it all went down, when his injuries are mostly healed and he's sleeping somewhat easier, Dean wakes up at ass in the morning to the heart-stopping sound of a Sam-sized crash. It's followed by loud scuffling, and Dean, already halfway down the hall, can hear Sam swearing a blue streak.

“Sammy?”

Dean tries the door. Locked, of course.

“I'm okay!” Sam yells.

“What the hell was that?” Dean calls, leaning against the door frame.

He hears Sam make a long, low noise of exertion, then grunt in pain.

“Sam?"

“Don't worry about it! Everything's fine!” 

But it doesn't sound fine. Dean trots back to his room and finds the lockpicking kit he never uses. It's a duplicate of Sam's. He always told himself he'd learn the finer points of B&E, but since Sam is always with him on the hunts that require lockpicking, Sam always does it. But how hard can it really be?

Dean crouches by the doorknob, sets his picks in, and begins clumsily feeling out the tumblers.

“Are you—Dean! Don't pick the fucking lock!”

“Tell me you're fine one more time,” Dean grunts, focused on his work. Stupid Men of Letters and their stupid antiquarian locks. It's nothing like the modern ones he's barely practiced on.

“I'm fine!”  

But Dean can still hear strain in Sam's voice, so he keeps at it.

Finally, finally, he hears a click that sounds like a winner—and wouldn't you know it, the knob turns.

“Dean, for fuck's sake, stay—”

The door swings open. Dean's jaw drops.

“—out,” Sam finishes, and sighs.

He's hanging half in, half out of his bed, long limbs sprawled every which way, hung up by the wrist that’s handcuffed to the headboard. His right leg is stretched out as far as it can go, and when Dean swings the door open wider, he sees the glint of a little metal key on the floor just out of Sam's reach.

He tries to stifle a laugh, but it explodes out of him anyway.

“I told you to stay out,” Sam snaps.

“Need some help?”

“Fuck you.”

Dean heads for the key. “What the hell is all this?” he asks, crouching to retrieve it. “You couldn't think of a better way to keep yourself from molesting me in my sleep?”

When he turns, he notices Sam looks a little green around the gills.

“Oh—you really couldn't?”

Sam just sighs again, exasperation and embarrassment in his tone and all over his face.

“Since you have zero listening skills,” he says, “and you're here anyway, get me out of this thing. It's cutting off my circulation.”

Climbing up on the bed, Dean inspects the handcuff, which is pulled so tight by Sam's weight that it's digging into the wood. Sam's hand is turning purple. As he searches for the keyhole, Sam begins to pull himself upright.

“I dunno how to feel about this,” Dean says. The keyhole is on the other side of the cuffs, and he tries to turn it toward them. Sam hisses. “What?”

“Hurts.”

“Try standing up.”

“I did try.” Sam bends himself around, clearly uncomfortable, crouching on the balls of his feet. “Move. Let me up there.”

Scooting back, Dean gingerly helps Sam get up on the bed. He's trying not to touch him too much, not missing the way Sam avoids touching him. After some awkward flopping and a few more muttered curses, Sam is flat on his back on the bed and red in the face.

“Okay,” he says. “Give me the key. I can unlock it now.”

Dean considers the little metal shape in his hand. Such a small thing—and he realizes as he perches there on the other side of the bed that it holds immeasurable power. He glances back over at Sam and isn't sure how he feels about the wide-open, ears-back look on his baby brother's face.

“Dean?” It comes out high. Hoarse.

Afraid.

“Give me the key.”

Inhaling deeply, Dean makes an abortive movement to do just that—but he smells something that gives him pause. It's a Sam-smell, warmth and spice, and something else entirely. He knows that smell. No, there's no way—

He glances down.

Sam is hard.

“No, don't—!”

But Dean is already down there, nosing at Sam's crotch like a hound, getting that scent from the source. He drops the key somewhere on the bed in favor of getting both hands on Sam's tense thighs, holding them open when they try to squeeze shut, mouthing over the cotton. Before long, it’s soaking wet. Sam's cock swells even harder, straining, and Dean goes to town on it, suckling until Sam moans.

“Ungh—Dean!”

He actually sounds like he might want Dean to stop, but he doesn't say that, so Dean does some Olympic-level mental gymnastics to turn it into permission. It seems like the Mark approves. The heat moving through his veins has a boost to it, like encouragement.

Some part of him knows he wouldn't be moving this fast if he wasn't saddled with an ancient curse. He'd still be wanting, though. Now that he knows what he's been missing, what he can have—he wants.

So he yanks Sam's briefs down under his balls in one rough movement, and licks up the whole long length of Sam's cock. The noise Sam makes sends the best kind of shiver down to his own crotch. It stokes the kindling fire there into the kind of raging inferno that devours whole cities. He needs.

“Dean,” Sam sobs in a delectable medley of pleasure and fear. “Dean, let me go.”

The handcuffs rattle, then vibrate, Sam going tense with a hiss as Dean begins to blow him in earnest. God, but Sam tastes amazing. Just as wet as before, just as hard, all for him. Dean licks over every inch of his baby brother's cock, taking it deep, deep into the cavern of his throat, over and over until Sam is properly crying and squirming beneath his restraining weight.

He pulls off. “You got lube, right?”

Sam gasps.

“Course you do.”

“Don't, Dean, please—”

“Shut up,” Dean says lovingly.

He sits up, and immediately, Sam scrambles, long legs thrashing, free hand patting frantically around the bed for the key. Dean lets him. He'll never find it in time. Dean is making a beeline for Sam's nightstand, the little drawer there, where he knows he'll find a stash of lube. It's the good thick kind, too.

Turning back to Sam, he gets the urge to pounce like an animal—so he does.

Sam lets out a yelp when he's pinned again. He flails with his free arm, trying to punch Dean or grab at his face, but Dean ranges up the whole lanky length of him and puts a stop to that. Propping himself up on his elbows around Sam's head, he strokes a few wayward strands of hair back from Sam's wild, terrified eyes.

“You don't know what you're missing, Sammy,” he says earnestly. “When you're asleep. You don't get to really feel it. But I'm gonna show you.”

“I know I came onto you then,” Sam says in a rush, “you told me I did, and maybe I feel—something, but Dean, I don't want it like th—”

The rest of whatever Sam was about to say is lost in Dean's all-consuming kiss. He resists, at first, but Dean puts all his skills to use, owning Sam's mouth so thoroughly that by the time he pulls back Sam is panting, dark-eyed and overwhelmed. Dean can feel how hard he is, how much harder he's gotten since this all started, and Dean digs his own hard-on into the furrow of Sam's pelvis to show him just how alike they are.

Sam's nostrils flare. “De—” He's silenced with a kiss. “Dean, d—” Another. “Sto—” And another. Every protest is smothered, again and again, until he's kissing back with what feels like an equal mix of desperation, arousal, and resignation.

Dean would rather he was into it, but figures he will be soon.

The click of the lube bottle cap is like a gunshot amid their panting. Sam flinches. Dean shushes against his lips, giving him another soft peck before sitting up and back. He's careful to keep Sam's free arm pinned beneath his knee.

The long, hard rod of Sam's cock is riding between his cheeks, and he wriggles just a little, feeling that delicious heat right where it belongs. But this isn't about him, he thinks. This is about Sam, who has been neglected in all of this by his own faulty design. Never let it be said that Dean blames Sam for everything; he's got a lot to answer for, but he isn't to blame for his ignorance here.

Soon, he'll see.

“Now, I know if I let this arm loose, you're gonna try to do some damage,” Dean says in a conversational tone. “So we're gonna take care of that real quick.”

Again, Sam doesn't find the key in time. Dean lashes his other arm to the headboard with the belt from his own jeans, discarded on the chair. Sam pulls against the leather until his veins are bulging, but there's no snapping it. Charlie's magic credit card got them actual quality gear just in time for it to work against him.

“I'd tie your legs, too, but I'm gonna need those,” Dean says. His erection hasn't flagged; in fact, seeing Sam all spread out like a crucifix is doing something to him in a very primal way. Sam is even doing the legs right, pressed together and twisted like a girl trying to protect her virtue.

Man, if Sam had a pussy, I'd really be in trouble, he thinks. I'd knock him up so good—

Dean blinks. That's new.

He chuckles. “You got me all messed up, Sammy.”

“You're fucked up, Dean,” Sam spits.

“Yeah—I guess I am.”

Then he's on top of Sam again. They wrestle; Sam's long legs sweeping around and down, trying to catch him in a hold, but Dean uses it against him and gets one folded up to Sam's chest. There's still underwear in his way, trapped around Sam's massive thighs, but Sam is squirming too much for there to be any hope of shucking them off—so in one fluid motion, Dean rips them in half, tossing the shreds to either side.

Freezing, Sam gapes down at him.

Then cold lube hits his hole, and he gasps aloud.

“No!” he shouts, beginning to struggle harder, but Dean is kneeling on one leg and pinning the other, so all Sam can really do is thrash his midsection around. That makes it way too easy for Dean to position a finger right on Sam's pucker and just wait for Sam to accidentally impale himself.

The shocked little noise that punches out of him when it does is goddamn delicious.

Dean slides the finger in further, down to his knuckles, working it around inside Sam with a mission. He finds that glorious little lump of nerves behind Sam's balls and strokes it lovingly, grinning the moment he hears Sam's panic turn to panting and heat.

“What the fuck?” Sam says, breathless. “What—”

“You like that?”

“No—ah, fuck—I don't wa—”

Dean rubs harder, circling, thrusting his fingers in and out over top of that spot.

“Holy shit, Dean—ah!”

There. That sounds better.

He gets two fingers in. A little hurt noise escapes, but right back to the prostate and Sam is moaning. Loud. It goes right to the base of Dean's dick and simmers there. Sam tosses his sweaty head on the pillow as Dean works him over, scissoring, petting his insides, getting him good and revved and ready.

By the time Dean is slicking up his cock, Sam looks out of his mind with want, red-faced and heavy-lidded, mouth hanging slack on spavined breaths.

“Say ‘pretty please,’ Sammy,” Dean teases.

“Hn, hn—no,” Sam chokes out, “hn—please, n—hn, no—”

“Good enough.”

Dean slams home with a grunt;

Sam arches his back up hard, and screams like he's dying.

God damn, Dean can't believe it. He's in heaven. Tight, sweet, heaven. Sam is burning up inside, hotter and tighter than anything Dean could have imagined, clenching around him in waves that might drown him if he doesn't fucking move. Quick thrust of his hips, then again, again, and Sam is jolted up the bed as he sobs, and swears, and takes it.

“You're so pretty,” Dean pants, jackhammering his cock as deep into Sam as he can. “So pretty, Sammy.”

Sam just lets out an anguished wail, neck stretched so far to the side his tendons look like they might snap. Regardless, his hips are working down to meet Dean's thrusts, slamming himself onto Dean's cock like a champ, taking as much as he's getting as he swears. Tears run down both sides of his face. His nose is running.

He's beautiful.

From this angle, Dean can't get up there to kiss him, and God, Dean wants to kiss him. Sam's teeth are bared; Dean would probably get bitten for his trouble, but the sense-memory of Sam's tongue against his makes him wild. He settled for pressing Sam's leg down harder, harder as he fucks his brother further up the bed, until Sam's breaths are rasping in his lungs. He's struggling for air, but still, he's meeting everything Dean is forcing on him with monumental force of his own.

“See?” Dean says. It comes out a growl. “See how good it can be?”

Sam just moans again, anguish and heat. His cock, trapped between them, is harder than Dean has ever known a cock could get. He shifts, adjust the angle, and fucks in with a vengeance, getting in there just right to grind against Sam's prostate every time. Sam's eyes nearly bulge out of his skull. His hips lose their rhythm.

There's no telling which of them comes first. Sam clenches around Dean so tight it might be cutting off his circulation, and Dean crests that peak so quick his eyes cross, pumping everything he has deep and slick inside. Sam comes with a howl of misery, smearing heat between them, thick and fast.

Dean doesn't want to stop. He's still hard. He could keep going. But Sam has fallen limp beneath him, mouth slack, eyes closed, and he's jolting like a rag doll. Dean realizes his muscles have all loosened just as he slows his rhythm to a crawl.

He stops.

“Sammy?”

Reaches up, and finds a pulse. It's barely there.

Sam is unconscious.

Pulling out, Dean lets his brother's leg fall free, and it splays out so far it nearly falls off the bed. Dean looks down, and sees in the scant light that something dark is glistening on his dick, on the sheets. Everywhere.

Oh, fuck. Sam is bleeding.

The Mark feeds a triumph of claiming at the same time Dean feels sick, dread pooling in his gut and shackling his limbs with lead as he darts over to Sam's dresser, pulls out one of his white undershirts, and wets it in the little sink every bedroom has in the corner. He returns to the bed, and pets the wet cloth gently over Sam's puffy, abused hole. The shirt soaks up red that gets more sporadic as he works. Eventually, it stops, but the damage remains.

You tore him up, Dean thinks to himself, hating it, reveling in it. You fucked him apart.

With a snort, Sam stirs. Dean abandons the shirt and in a flash, has Sam's head in his hands.

“Sammy?”

“Dean,” Sam murmurs groggily.

Reality hits him like a visible thunderclap. He tenses. Flails. Yowls like a punted cat.

Dean is yanking the covers from beneath him, and turning on the bedside lamp to find the little key that just fell to the ground with a sharp little tink! He looses the belt, unlocks the handcuff, and takes two quick steps back, just waiting for Sam to lunge—

But Sam chokes out a wretched noise, rolls into a ball, and starts shaking. Crying. Huge, wracking sobs like he just lost everything.

He did. You fucking took it all away. You monster, Dean thinks, atop a spreading satisfaction at a job well done. I'm still a demon, he thinks, but knows it isn't true, because if he was then he wouldn't care.

Part of him doesn't.

Pulling the blankets back up, Dean slides beneath them, covering both him and Sam as he pulls Sam's shivering frame into his arms. Sam lets him. Clings like he did when he was young, when none of this was even a thought they were capable of having. Dean strokes his head and whispers how good he is, how well he took it, and wasn't it awesome?

Sam just buries his face in Dean's armpit, crying, and doesn't say a word.

- - - - - - -

Sobs turn to whimpers, to nothing at all. When Sam can finally stand, he bolts to the bathroom to vomit. Dean is amazed when, ten or so minutes later, he actually comes back in one of the Men of Letters’ bathrobes. He haunts the doorway like he can't decide whether to run, or give up and come in.

Before Dean can pat the bed lasciviously, Sam says, his voice shot, “I know this isn't really you.” He sounds moments away from crying again. He'll probably cry off and on for days.

Isn't it, though? Dean thinks. He feels so alive, electrical and bright, energy under his skin like live wires. Maybe I wasn't me before. Maybe I needed this.

“We're going to find the Book of the Damned, and I'm going to save you.”

What if I don't want to be saved? What if I like the disease?

“I'll save you,” Sam repeats, like he heard, “but I'll never fucking forgive you.”

Still buzzing with afterglow, sweaty and sated, Dean can't think of a single reason why he'd want to be free of the Mark at this point. After all, it gave him Sam on a level he never would have reached otherwise.

He gives Sam a look that says this, and Sam shudders, but doesn't look away.

Dean shrugs.

“That's fair.”